The video below, which was posted to YouTube November 14, features photos that document the rare opportunity Norvell and Perez had to dismantle the original guitars, dubbed "Blue-Mustank" and "Oranj-Stang," to ascertain wiring schemes and pickup configurations.

"On the In Utero tour that followed the album, Kurt favored a quiver of modified Fender Mustang guitars as main instruments for his sonic attack," writes Fender on its website.

"A few years ago, Fender took on the challenge of authentically replicating the specifications of these historic instruments for the Kurt Cobain Signature Mustang guitars. It meant unearthing a music history time capsule that for years had been out of the public eye."

It's a shame the video isn't longer and doesn't show more of the insides of the guitars.